Pen



FIG. 1 is an upper front right perspective view of a pen showing my new design;

FIG. 2 is an exploded lower front left perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a rear elevation view thereof;

FIG. 7 is an enlarged top plan view thereof; and,

FIG. 8 is a left side elevation view thereof.

The broken lines showing a writing tip and grip in FIG. 2 illustrate environmental matter and form no part of the claimed design. The broken lines shown in the top of the cap in FIG. 7, which define the bounds of the claimed design, form no part thereof. 

The ornamental design for a pen, as shown and described. 